Seasonal Variability of Salt Transport During the Indian Ocean Monsoons

Abstract

The seasonal variability of salinity transport in the Indian Ocean is investigated using the high-resolution global HYbrid Coordinate Ocean Model (HYCOM) Mechanisms and physical parameters that control the salinity budget are examined. Results show the influence of freshwater forcing and zonal advection as the dominant mechanisms of sea surface salinity (SSS) variability. Precipitation is highest in the eastern Bay of Bengal (BoB), where it shows seasonal variation, and in the south equatorial eastern Indian Ocean (EIO), where it was consistently high year-round. These patterns result in significant seasonal variation in the SSS in the BoB and almost no variation in the EIO Zonal SSS transport was higher than meridional SSS transport with the strongest seasonality observed along the Sri Lankan region. Results of depth-integrated transport show northward salt transport in the bottom layers and a southward salt transport in the surface layers. The 4 year mean net flux of depth-integrated salt transport was southward ( 154.8 * 106 kg/s to -552.4 x 106 kg/s) at all latitudes except at 20 N. where it was northward (396 * 106 kg/s). Transport generally increases southward with the highest transports occurring in the south (10 S -35 S) and a maximum at 30 S. Analyses of meridional Ekman volume and salt transport show a predominantly southward transport, an indication of the strong influence of SW monsoonal winds. It is anticipated that this study will be useful in computing salt transport using satellite-derived salinity data from the European Space Agency (ESA) Soil Moisture and Ocean Salinity (SMOS) and NASA Aquarius salinity missions.

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Document Details

Document Type
Technical Report
Publication Date
Aug 27, 2011
Accession Number
ADA555622

Entities

People

  • Bulusu Subrahmanyam
  • Ebenezer S. Myadjro
  • Jay F. Shriver

Organizations

  • United States Naval Research Laboratory

Tags

Communities of Interest

  • Materials and Manufacturing Processes
  • Space

DTIC Thesaurus Topics

  • Advection
  • Arabian Sea
  • Climate Change
  • Databases
  • Drops
  • Grids
  • High Resolution
  • Indian Ocean
  • Latitude
  • Ocean Currents
  • Oceanography
  • Oceans
  • Ridges
  • Sea Water
  • Seasonal Variations
  • Terrain
  • Topography

Fields of Study

  • Environmental science

Readers

  • Atmospheric Science/Meteorology
  • Coastal Oceanography
  • Oceanography.

Technology Areas

  • Space